We have investigated the recessive mouse mutant synpolydactyly homolog (spdh) as a model for human synpolydactyly (SPD). As in human SPD, the spdh phenotype consists of central polydactyly, syndactyly and brachydactyly and is caused by the expansion of a polyalanine encoding repeat in the 5' region of the Hoxd13 gene. We performed a detailed phenotypic and functional analysis of spdh/spdh embryos using skeletal preparations, histology, in situ hybridization, BrdU labeling of proliferating cells… CONTINUE READING